www: Use a modern menu style

git-svn-id: https://llvm.org/svn/llvm-project/polly/trunk@197722 91177308-0d34-0410-b5e6-96231b3b80d8
www: Rename menu items

git-svn-id: https://llvm.org/svn/llvm-project/polly/trunk@197723 91177308-0d34-0410-b5e6-96231b3b80d8
www: shorten menu entry

git-svn-id: https://llvm.org/svn/llvm-project/polly/trunk@197724 91177308-0d34-0410-b5e6-96231b3b80d8